Report server spawning multiple w3wp.exe threads

We have Win2003 SP1, SQL 2000 SP4, RS 2000 SP2 installed on our dev
machine and it works ok - having problems using anonamous access under
IIS but that is another issue.....
On our production server ( win2003 SP1, SQL 2000 SP4 ) we installed RS
2000 and SP2, accepting all the default installation options accept
SSL, and we have the following problems....
When we try to access http:\\servername\reports it takes a good few
minutes to load the web page, after asking for a domain user account,
and then the whole server runs like a dog.
Just getting to the first web page creates 12-15 copies of w3wp.exe,
each of which swallow between 20 and 130 MB of memory, and ramps up the
CPU usage.
I you try to upload a report, or access an existing report it spawns
off another 8-10 copies of w3wp.exe and eats more memory, and seriously
slows the server down.
The only way to release the resources it has useems to be to restart
IIS.
I "think" that this may be due to some hardening or lock down of
production server, but I am struggling on what to do next.
The RS logs do not seem to show any problems, but the Win App log shows
"ID 124 ReportServer Service has been activated" 5-6 times for every
action you take against reporting services.
I have been through the "checking reporting services is installed"
guides and it all seems ok, so there is something key I am missing here
!!!
Anyone else had similar problems and found the solution, or could at
least point me in the right direction to progress this issue !An update...
Thanks our freinds at the hosting company, it turns out this was all
due to .Net framework and IIS
We have apps running under 1.1 and 2.0 frameworks, and RS was set to
use default app pool on the IIS config.
Created a new app pool, and let both RS directories use that instead -
bingo !
Lots of w3wp.exe still created, but not hosing the box, and the number
goes up and down as usage changes.
Advice has been to create a new app pool just for reporting services,
as it is a hungry beast !